The present invention relates to an optoelectronic unit and a transparent conductive substrate of the same, and more particularly, to a transparent conductive substrate used as an upper cover for an optoelectronic element, and to an optoelectronic unit having the transparent conductive substrate.
Generally speaking, an optoelectronic device usually comprises a semiconductor optoelectronic element, and the property of the optoelectronic device is closely related to that of the optoelectronic element. Currently, one of the most commonly-used optoelectronic elements is a diode chip, which can be roughly divided into a light-emitting diode (LED) chip and a photodiode chip. Correspondingly, the optoelectronic device-can be roughly divided into a light-emitting element, such as a LED and a laser diode (LD), or a photodiode used as a photosensitive element, such as a photodetector and a solar cell, wherein the photodetector can be a photodiode (PD) or a positive-intrinsic-negative (PIN) diode, etc.
Herein a LED is taken as an example, and the structure thereof can be referred to U.S. Pat. No. 5,998,952. Such as shown in FIG. 1, a LED comprises a coating resin 101, a diode chip 102, a conductive wire 103, a molding material 104, a lead frame 105 and an inner lead 106, wherein the lead frame 105 comprises a base 105a and a lead 105b. Such as shown in FIG. 1, the coating resin 101 is filled in the base 105a and covers the diode chip 102, to prevent the diode chip 102 from contacting oxygen or moisture, thereby protecting the diode chip 102. The coating resin 101 is generally made of transparent material, such as epoxy resin, urea resin or glass, etc. Further, in the aforementioned LED shown in FIG. 1, light emitted by the diode chip 102 toward the base 105a cannot reach the outside, so that the emission light intensity and light emission efficiency are affected.
Furthermore, the photosensitive element can be a photodiode, a PIN diode, a phototransistor, a photonic crystal or a solar cell. The photodiode comprises a photodiode chip, which is a diode sensitive to light. When light directly irradiates a PN junction of the photodiode chip, the reverse current will be enlarged, and the photodiode is operated at the condition of reverse bias. The packaging of the photodiode chip is similar to that of the LED chip. A coating resin can be coated on the photodiode chip to prevent the photodiode chip from contacting oxygen or moisture, thereby protecting the photodiode chip.
However, although by using the coating resin coated to cover a LED chip or a photodiode chip, the chip can be protected from being oxidized or corroded by oxygen or moisture, etc., yet the coating resin still will be deteriorated and cured by the influence of heat and radiation, and the coating resin has poor heat-dissipation and little endurance to UV light, so that the coating resin is susceptible to the damage caused by UV rays in sunshine. Once the coating resin starts deteriorating, the chip covered thereby will be affected and damaged. Especially for the element of which the waveband of light emitted is below that of blue light (wherein the wavelength of emitted light is smaller than 480 nm), because the LED chip thereof has the attribute of spontaneous irradiation, and additionally, the light traveling path thereof is concentrated within a specific angle so as to result in high light emission intensity, consequently, the damage to the coating resin is more sever. Besides, for the photodiode, one side thereof facing the base cannot receive external light because of packaging, so that the aforementioned method adopted also has great influence on the photosensitivity of the photodiode.
To sum up, it is quite important about how to provide an optoelectronic device for protecting the optoelectronic element from damage and influence caused by the deterioration of the coating resin, and meanwhile promoting the light emission (or detection) efficiency, operation stability and operation life, etc. for the optoelectronic element (or a lightemitting element), so as to promote the reliability of the element.
For overcoming the conventional problems described in the aforementioned background, one object of the present invention is to provide an optoelectronic unit and a transparent conductive substrate of the same, thereby isolating an optoelectronic element.
It is the other object of the present invention to provide an optoelectronic unit and a transparent conductive substrate of the same, for enabling active optoelectronic elements and passive optoelectronic elements to emit light outwards or receive light from two sides thereof arbitrarily.
According to the aforementioned objects, the present invention provides a transparent conductive substrate of an optoelectronic unit, which is characterized in that an optoelectronic element is implemented on a transparent conductive substrate, and then the transparent conductive substrate is turned upside down to cover a base, so that the optoelectronic element is located in a substantially closed space. As to the transparent conductive substrate of the optoelectronic unit according to the present invention, it comprises: a transparent plate, a transparent electrode film, an insulation part, and a bounding pad, wherein the transparent electrode film and the insulation part are formed on the transparent plate, and the insulation part divides the transparent electrode film into two areas that are not electrically conducted to each other, and the bounding pad is formed on an area of the transparent electrode film.
According to the aforementioned objects, the present invention provides an optoelectronic unit comprising: a transparent conductive substrate, an optoelectronic element arid a conductive wire, wherein the structure of the transparent conductive substrate is descried as above, and the insulation part divides the transparent conductive film into a first transparent electrode film area and a second transparent electrode film area that ate not electrically conducted to each other, and the bounding pad is formed on the second transparent electrode film area, and one electrode of the optoelectronic element is electrically connected to the first transparent electrode film area, and the conductive wire is electrically connected between the other electrode of the optoelectronic element and the bounding pad. Further, the present invention can have a base, on which the aforementioned transparent conductive substrate is disposed after being turned upside down, and a closed space is formed between the transparent conductive substrate and the base, wherein the aforementioned bounding pad, the optoelectronic element and the conductive wire are located in the closed space.
Moreover, in the present invention, the transparent electrode film, the first transparent electrode film area and the second transparent electrode film area can be made of transparent film material selected from a group consisting of such as ITO, ZnO, CTO, IZO, ZrO2, AZO, and the compound layer thereof. Besides the aforementioned materials, a thin metal electrode can be used as the transparent film electrode, wherein the thin metal electrode is formed by a plurality of metal layers arbitrarily selected from a group consisting of nickel, silver, aluminum, titanium, chromium, gold, platinum, tungsten, tungsten silicide, zinc, imdium and aluminum-silicon alloys, etc. Meanwhile, the aforementioned optoelectronic can be a LED element or a photosensitive element.
Since the optoelectronic element of the present invention is implemented on a transparent conductive substrate, the optoelectronic element can be isolated from the surroundings. Also, since the transparent conductive substrate allows light to pass through, the LED element can emit light outwards from its two sides, and photosensitive element can also receive light from its two sides.